A whining alternator.

[Hot Rod Roy]

Who knows why alternators whine? I had to replace my alternator, and my new one whines at low speed. It works fine, and I've taken it apart and checked for bad bearings, brushes, or internal rotating parts touching something, but everything looks good. Any ideas?

:confused

 

[G Winter]

Often new brushes whine untill they get seated. Did you notice if the brushe ends were flat or concaved ? If they are concaved you may be able to get rid of the noise by lightly filing the contact edges of the brushes. I would be a little suspect of a bearing though. I would talk to the supplier about it and see what they think.If it don't go away I would ask about a replacement before warrenty is off.


Glenn

 

[Hot Rod Roy]

A Whiner

Glen, you were right. The ends of the new brushes are concaved, to match the shape of the slip rings, but now that they have had a chance to wear in to seat the brushes, they are running quietly! Thanks for the suggestions!